Novel light sources such as light sources based on light emitting diodes (LEDs) or discharge lamps become increasingly more popular. Converters for such light sources are operative to feed an output current to a light-emitting means, e.g. to an inorganic or organic light emitting diode (LED).
It is desirable that a converter can be used for operating in conjunction with a wide variety of light emitting means. For illustration, LED-based light emitting means may have a wide variety of different load voltages, depending on the types of LEDs which are used and the way in which the LEDs are interconnected. In order to accommodate the different load voltages, closed-loop control schemes may be used in which an output current of the converter is measured and used in a feedback loop. The measurement of the output current may add to the complexity and costs of the converter, which is undesirable.